The present implementations relate to a digitizer of a computer device, and more particularly, to techniques for performing fast pen detection at a digitizer.
Electromagnetic pens or styluses are known in the art for use and control of a digitizer. Position detection of the pen provides input to a computing device associated with the digitizer and is interpreted as user commands. Position detection is performed while the pen tip is either touching and/or hovering over a detection surface of the digitizer. Often, the digitizer is integrated with a display screen and a position of the pen over the screen is correlated with information portrayed on the screen.
A digitizer may operate in a search mode or a tracking mode. The digitizer operates in a search mode when there is no communication or contact with the pen, or the communication or contact with the pen is lost and the digitizer is searching for a transmission signal, such as a beacon, from the pen. Once the digitizer finds the transmission signal from the pen, the digitizer performs a synchronization with the pen and the digitizer transitions to a tracking mode. In the tracking mode, the digitizer is in synchronization with the transmission signal from the pen and can receive information from the pen.
However, the digitizer may lose contact with the pen during gestures and may get out of sync, i.e., lose synchronization. This may result in lost strokes from the pen which may affect the robustness (e.g., performance) of the digitizer. Therefore, there is a need for an improved pen detection at a digitizer of a computer device.